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authorshmel1k <shmel1k@ydb.tech>2022-09-02 12:44:59 +0300
committershmel1k <shmel1k@ydb.tech>2022-09-02 12:44:59 +0300
commit90d450f74722da7859d6f510a869f6c6908fd12f (patch)
tree538c718dedc76cdfe37ad6d01ff250dd930d9278 /contrib/libs/clapack/zlartg.c
parent01f64c1ecd0d4ffa9e3a74478335f1745f26cc75 (diff)
downloadydb-90d450f74722da7859d6f510a869f6c6908fd12f.tar.gz
[] add metering mode to CLI
Diffstat (limited to 'contrib/libs/clapack/zlartg.c')
-rw-r--r--contrib/libs/clapack/zlartg.c285
1 files changed, 285 insertions, 0 deletions
diff --git a/contrib/libs/clapack/zlartg.c b/contrib/libs/clapack/zlartg.c
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+/* zlartg.f -- translated by f2c (version 20061008).
+ You must link the resulting object file with libf2c:
+ on Microsoft Windows system, link with libf2c.lib;
+ on Linux or Unix systems, link with .../path/to/libf2c.a -lm
+ or, if you install libf2c.a in a standard place, with -lf2c -lm
+ -- in that order, at the end of the command line, as in
+ cc *.o -lf2c -lm
+ Source for libf2c is in /netlib/f2c/libf2c.zip, e.g.,
+
+ http://www.netlib.org/f2c/libf2c.zip
+*/
+
+#include "f2c.h"
+#include "blaswrap.h"
+
+/* Subroutine */ int zlartg_(doublecomplex *f, doublecomplex *g, doublereal *
+ cs, doublecomplex *sn, doublecomplex *r__)
+{
+ /* System generated locals */
+ integer i__1;
+ doublereal d__1, d__2, d__3, d__4, d__5, d__6, d__7, d__8, d__9, d__10;
+ doublecomplex z__1, z__2, z__3;
+
+ /* Builtin functions */
+ double log(doublereal), pow_di(doublereal *, integer *), d_imag(
+ doublecomplex *), sqrt(doublereal);
+ void d_cnjg(doublecomplex *, doublecomplex *);
+
+ /* Local variables */
+ doublereal d__;
+ integer i__;
+ doublereal f2, g2;
+ doublecomplex ff;
+ doublereal di, dr;
+ doublecomplex fs, gs;
+ doublereal f2s, g2s, eps, scale;
+ integer count;
+ doublereal safmn2;
+ extern doublereal dlapy2_(doublereal *, doublereal *);
+ doublereal safmx2;
+ extern doublereal dlamch_(char *);
+ doublereal safmin;
+
+
+/* -- LAPACK auxiliary routine (version 3.2) -- */
+/* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
+/* November 2006 */
+
+/* .. Scalar Arguments .. */
+/* .. */
+
+/* Purpose */
+/* ======= */
+
+/* ZLARTG generates a plane rotation so that */
+
+/* [ CS SN ] [ F ] [ R ] */
+/* [ __ ] . [ ] = [ ] where CS**2 + |SN|**2 = 1. */
+/* [ -SN CS ] [ G ] [ 0 ] */
+
+/* This is a faster version of the BLAS1 routine ZROTG, except for */
+/* the following differences: */
+/* F and G are unchanged on return. */
+/* If G=0, then CS=1 and SN=0. */
+/* If F=0, then CS=0 and SN is chosen so that R is real. */
+
+/* Arguments */
+/* ========= */
+
+/* F (input) COMPLEX*16 */
+/* The first component of vector to be rotated. */
+
+/* G (input) COMPLEX*16 */
+/* The second component of vector to be rotated. */
+
+/* CS (output) DOUBLE PRECISION */
+/* The cosine of the rotation. */
+
+/* SN (output) COMPLEX*16 */
+/* The sine of the rotation. */
+
+/* R (output) COMPLEX*16 */
+/* The nonzero component of the rotated vector. */
+
+/* Further Details */
+/* ======= ======= */
+
+/* 3-5-96 - Modified with a new algorithm by W. Kahan and J. Demmel */
+
+/* This version has a few statements commented out for thread safety */
+/* (machine parameters are computed on each entry). 10 feb 03, SJH. */
+
+/* ===================================================================== */
+
+/* .. Parameters .. */
+/* .. */
+/* .. Local Scalars .. */
+/* LOGICAL FIRST */
+/* .. */
+/* .. External Functions .. */
+/* .. */
+/* .. Intrinsic Functions .. */
+/* .. */
+/* .. Statement Functions .. */
+/* .. */
+/* .. Save statement .. */
+/* SAVE FIRST, SAFMX2, SAFMIN, SAFMN2 */
+/* .. */
+/* .. Data statements .. */
+/* DATA FIRST / .TRUE. / */
+/* .. */
+/* .. Statement Function definitions .. */
+/* .. */
+/* .. Executable Statements .. */
+
+/* IF( FIRST ) THEN */
+ safmin = dlamch_("S");
+ eps = dlamch_("E");
+ d__1 = dlamch_("B");
+ i__1 = (integer) (log(safmin / eps) / log(dlamch_("B")) / 2.);
+ safmn2 = pow_di(&d__1, &i__1);
+ safmx2 = 1. / safmn2;
+/* FIRST = .FALSE. */
+/* END IF */
+/* Computing MAX */
+/* Computing MAX */
+ d__7 = (d__1 = f->r, abs(d__1)), d__8 = (d__2 = d_imag(f), abs(d__2));
+/* Computing MAX */
+ d__9 = (d__3 = g->r, abs(d__3)), d__10 = (d__4 = d_imag(g), abs(d__4));
+ d__5 = max(d__7,d__8), d__6 = max(d__9,d__10);
+ scale = max(d__5,d__6);
+ fs.r = f->r, fs.i = f->i;
+ gs.r = g->r, gs.i = g->i;
+ count = 0;
+ if (scale >= safmx2) {
+L10:
+ ++count;
+ z__1.r = safmn2 * fs.r, z__1.i = safmn2 * fs.i;
+ fs.r = z__1.r, fs.i = z__1.i;
+ z__1.r = safmn2 * gs.r, z__1.i = safmn2 * gs.i;
+ gs.r = z__1.r, gs.i = z__1.i;
+ scale *= safmn2;
+ if (scale >= safmx2) {
+ goto L10;
+ }
+ } else if (scale <= safmn2) {
+ if (g->r == 0. && g->i == 0.) {
+ *cs = 1.;
+ sn->r = 0., sn->i = 0.;
+ r__->r = f->r, r__->i = f->i;
+ return 0;
+ }
+L20:
+ --count;
+ z__1.r = safmx2 * fs.r, z__1.i = safmx2 * fs.i;
+ fs.r = z__1.r, fs.i = z__1.i;
+ z__1.r = safmx2 * gs.r, z__1.i = safmx2 * gs.i;
+ gs.r = z__1.r, gs.i = z__1.i;
+ scale *= safmx2;
+ if (scale <= safmn2) {
+ goto L20;
+ }
+ }
+/* Computing 2nd power */
+ d__1 = fs.r;
+/* Computing 2nd power */
+ d__2 = d_imag(&fs);
+ f2 = d__1 * d__1 + d__2 * d__2;
+/* Computing 2nd power */
+ d__1 = gs.r;
+/* Computing 2nd power */
+ d__2 = d_imag(&gs);
+ g2 = d__1 * d__1 + d__2 * d__2;
+ if (f2 <= max(g2,1.) * safmin) {
+
+/* This is a rare case: F is very small. */
+
+ if (f->r == 0. && f->i == 0.) {
+ *cs = 0.;
+ d__2 = g->r;
+ d__3 = d_imag(g);
+ d__1 = dlapy2_(&d__2, &d__3);
+ r__->r = d__1, r__->i = 0.;
+/* Do complex/real division explicitly with two real divisions */
+ d__1 = gs.r;
+ d__2 = d_imag(&gs);
+ d__ = dlapy2_(&d__1, &d__2);
+ d__1 = gs.r / d__;
+ d__2 = -d_imag(&gs) / d__;
+ z__1.r = d__1, z__1.i = d__2;
+ sn->r = z__1.r, sn->i = z__1.i;
+ return 0;
+ }
+ d__1 = fs.r;
+ d__2 = d_imag(&fs);
+ f2s = dlapy2_(&d__1, &d__2);
+/* G2 and G2S are accurate */
+/* G2 is at least SAFMIN, and G2S is at least SAFMN2 */
+ g2s = sqrt(g2);
+/* Error in CS from underflow in F2S is at most */
+/* UNFL / SAFMN2 .lt. sqrt(UNFL*EPS) .lt. EPS */
+/* If MAX(G2,ONE)=G2, then F2 .lt. G2*SAFMIN, */
+/* and so CS .lt. sqrt(SAFMIN) */
+/* If MAX(G2,ONE)=ONE, then F2 .lt. SAFMIN */
+/* and so CS .lt. sqrt(SAFMIN)/SAFMN2 = sqrt(EPS) */
+/* Therefore, CS = F2S/G2S / sqrt( 1 + (F2S/G2S)**2 ) = F2S/G2S */
+ *cs = f2s / g2s;
+/* Make sure abs(FF) = 1 */
+/* Do complex/real division explicitly with 2 real divisions */
+/* Computing MAX */
+ d__3 = (d__1 = f->r, abs(d__1)), d__4 = (d__2 = d_imag(f), abs(d__2));
+ if (max(d__3,d__4) > 1.) {
+ d__1 = f->r;
+ d__2 = d_imag(f);
+ d__ = dlapy2_(&d__1, &d__2);
+ d__1 = f->r / d__;
+ d__2 = d_imag(f) / d__;
+ z__1.r = d__1, z__1.i = d__2;
+ ff.r = z__1.r, ff.i = z__1.i;
+ } else {
+ dr = safmx2 * f->r;
+ di = safmx2 * d_imag(f);
+ d__ = dlapy2_(&dr, &di);
+ d__1 = dr / d__;
+ d__2 = di / d__;
+ z__1.r = d__1, z__1.i = d__2;
+ ff.r = z__1.r, ff.i = z__1.i;
+ }
+ d__1 = gs.r / g2s;
+ d__2 = -d_imag(&gs) / g2s;
+ z__2.r = d__1, z__2.i = d__2;
+ z__1.r = ff.r * z__2.r - ff.i * z__2.i, z__1.i = ff.r * z__2.i + ff.i
+ * z__2.r;
+ sn->r = z__1.r, sn->i = z__1.i;
+ z__2.r = *cs * f->r, z__2.i = *cs * f->i;
+ z__3.r = sn->r * g->r - sn->i * g->i, z__3.i = sn->r * g->i + sn->i *
+ g->r;
+ z__1.r = z__2.r + z__3.r, z__1.i = z__2.i + z__3.i;
+ r__->r = z__1.r, r__->i = z__1.i;
+ } else {
+
+/* This is the most common case. */
+/* Neither F2 nor F2/G2 are less than SAFMIN */
+/* F2S cannot overflow, and it is accurate */
+
+ f2s = sqrt(g2 / f2 + 1.);
+/* Do the F2S(real)*FS(complex) multiply with two real multiplies */
+ d__1 = f2s * fs.r;
+ d__2 = f2s * d_imag(&fs);
+ z__1.r = d__1, z__1.i = d__2;
+ r__->r = z__1.r, r__->i = z__1.i;
+ *cs = 1. / f2s;
+ d__ = f2 + g2;
+/* Do complex/real division explicitly with two real divisions */
+ d__1 = r__->r / d__;
+ d__2 = d_imag(r__) / d__;
+ z__1.r = d__1, z__1.i = d__2;
+ sn->r = z__1.r, sn->i = z__1.i;
+ d_cnjg(&z__2, &gs);
+ z__1.r = sn->r * z__2.r - sn->i * z__2.i, z__1.i = sn->r * z__2.i +
+ sn->i * z__2.r;
+ sn->r = z__1.r, sn->i = z__1.i;
+ if (count != 0) {
+ if (count > 0) {
+ i__1 = count;
+ for (i__ = 1; i__ <= i__1; ++i__) {
+ z__1.r = safmx2 * r__->r, z__1.i = safmx2 * r__->i;
+ r__->r = z__1.r, r__->i = z__1.i;
+/* L30: */
+ }
+ } else {
+ i__1 = -count;
+ for (i__ = 1; i__ <= i__1; ++i__) {
+ z__1.r = safmn2 * r__->r, z__1.i = safmn2 * r__->i;
+ r__->r = z__1.r, r__->i = z__1.i;
+/* L40: */
+ }
+ }
+ }
+ }
+ return 0;
+
+/* End of ZLARTG */
+
+} /* zlartg_ */